It’s a big week for lab-grown body parts. Earlier, we reported that researchers have successfully transplanted replacement vaginas into patients with MRKH syndrome, and now we find that engineered cartilage tissue for nasal reconstruction have been implanted in human patients for the first time.
A team led by Ivan Martin from University of Basel in Switzerland recruited 5 volunteers, ages 76 to 88, who suffered defects to their nose after surgery to remove non-melanoma skin cancer tumors. This cancer is the most common on the nose because of its exposure to the sun -- specifically on the alar wings (the part that lifeguards in old movies covered with white, opaque sunblock). To remove the tumor completely, surgeons often have to cut away parts of the cartilage. With the standard technique, grafts for reconstruction are taken from other cartilaginous parts of the body, such as the ears or the ribs.
To see if there was another way to reconstruct the nose without an additional surgery, the team extracted cartilage cells (called chondrocytes) from the patient’s own nasal septum, harvested during their tumor biopsy sample. Over the course of a month, these cells were multiplied, expanded, and finally, seeded onto a collagen membrane, which acts like a scaffold. These were cultured in a serum for an additional two weeks, and then the resulting engineered cartilage grafts (with dimensions 25 mm × 25 mm × 2 mm) where shaped according to the patient’s defect. These were then implanted after tumor excision, and covered with skin from their forehead.
Half a year later, the reconstructed tissues showed “fibromuscular” fatty structures, which are typical for healthy alar lobules. After a year, all the patients were satisfied with the aesthetics and functioning of their reconstructed nose; no side effects have been reported. The same engineered grafts are being tested now in knees.
“Now that we have demonstrated this is safe and feasible, we can use [this technique] for more complicated clinical needs,” Martin tells Boston Globe. While scientists are slowly gaining more expertise in making body parts, it could take another couple of decades before the process becomes mainstream. “It’s not a trivial thing to engineer a functional tissue,” he adds.
This procedure, together with the lab-grown vagina transplants, is detailed in the current edition of The Lancet.
Image: Department of Biomedicine at the University of Basel